Since I had no detailed measurements, I had to build each element based on comparisons to the sizes of established elements. For instance...Link (via The Disney Blog)
a corner of the mansion may have thirteen cornerstones going up its spine, and the level of the front door is three cornerstones above ground level. So, to calculate the height of each of the seven steps leading to the front door, I had to divide the height of three cornerstones, by seven.
So let's just skip to the nearly completed Haunted Mansion model. I say, "nearly completed" because, to date, I've only completed the front facade of the mansion. I'm still building my own version of the rear of the house, and the grounds. I'll post the new models as soon as they're complete.